Kentaro Kai

Enhanced miR-210 expression promotes the pathogenesis of endometriosis through activation of signal transducer and activator of transcription 3

STUDY QUESTION What are the roles of the microRNA miR-210-an miRNA that is up-regulated in endometriotic cyst stromal cells (ECSCs)-in the pathogenesis of endometriosis? SUMMARY ANSWER Up-regulated miR-210 expression in ECSCs is involved in their proliferation, resistance to apoptosis and angiogenesis through signal transducer and activator of transcription (STAT) 3. WHAT IS KNOWN ALREADY In the pathogenesis of endometriosis, a number of roles for microRNAs (miRNAs) are becoming apparent. STUDY DESIGN, SIZE, DURATION ECSCs and normal endometrial stromal cells (NESCs) were isolated from ovarian endometriotic tissues (patients aged 24-40 years undergoing salpingo-oophorectomy or evisceration for the treatment of ovarian endometriotic cysts, n = 10) and the eutopic endometrial tissues without endometriosis (premenopausal patients aged 35-45 years undergoing hysterectomies for subserousal leiomyoma, n = 13), respectively. PARTICIPANTS/MATERIALS, SETTING, METHODS We used a global gene expression microarray technique to identify downstream targets of miR-210, and we assessed the functions of miR-210 in the pathogenesis of endometriosis by using the miR-210-transfected NESCs. MAIN RESULTS AND THE ROLE OF CHANCE Gene expression microarray analysis revealed that one of the key target molecules of miR-210 is STAT3. In the NESCs, in comparison to the control, miR-210 transfection resulted in the induction of cell proliferation (P < 0.0005), the production of vascular endothelial cell growth factor (VEGF) (P < 0.0005) and the inhibition of apoptosis (P < 0.05) through STAT3 activation [increased levels of mRNA (P < 0.0005), and protein (P < 0.005)]. In the ECSCs, inhibitors of STAT3 inhibited the cell proliferation and VEGF production (P < 0.05), and induced the apoptosis of these cells (P < 0.05). LIMITATIONS, REASONS FOR CAUTION The roles of aberrant miR-210 expression were investigated only in the stromal component of ectopic and eutopic endometrium. Control endometrial tissues were obtained from premenopausal patients who had subserosal leiomyoma and NESC gene expression patterns may be altered in these women. Furthermore, the effects of STAT3 inhibitors were evaluated only in ECSCs and not in NESCs. WIDER IMPLICATIONS OF THE FINDINGS The present findings indicate that miR-210 induces NESCs to differentiate into the endometriotic phenotype and we speculate that up-regulated miR-210 expression in ECSCs is involved in the creation of the endometriosis-specific cellular dysfunctions through epigenetic mechanisms. The data indicate that STAT3 inhibitors may be promising candidates for the treatment of endometriosis. STUDY FUNDING/COMPETING INTERESTS This work was supported in part by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (no. 13237327 to K.N., no. 25861500 to Y.K. and no. 23592407 to H.N.). There are no conflicts of interest to declare.

Aberrant histone modification in endometriosis.

Accumulating evidence suggests that epigenetic aberrations play definite roles in the pathogenesis of endometriosis. These include aberrations in genomic DNA methylation, microRNA expression, and histone modification. The aberrant histone modification status and the aberrant expression of histone deacetylases, which regulate histone acetylation, in endometriosis are the focus of this review. Herein, we summarize the recent studies in the following areas: (i) hyperacetylation of histones located in the promoter lesions of G-protein-coupled estrogen receptor 1, steroidogenic factor-1, and hypoxia-inducible factor-1 alpha genes and (ii) hypoacetylation of histones located in the promoter lesions of estrogen receptor alpha, homeobox A10, CCAAT/enhancer-binding protein alpha, p16(INK4a), p21(Waf1/Cip1), p27(Kip1), checkpoint kinase 2, death receptor 6, and E-cadherin genes. Further research from the viewpoint of epigenetics may lead to the identification of the candidate molecules that are aberrantly expressed in endometriosis and may help elucidate the pathogenesis of this disease. In addition, epigenetic drugs (including histone deacetylase inhibitors) show promise for the treatment of endometriosis by amending the expression of these epigenetically dysregulated genes.

CCAAT/enhancer-binding protein α is epigenetically silenced by histone deacetylation in endometriosis and promotes the pathogenesis of endometriosis.

CONTEXT Accumulating evidence suggests that various epigenetic aberrations play definite roles in the pathogenesis of endometriosis. OBJECTIVE The objective of the study was to determine the epigenetically silenced genes by histone deacetylation in endometriosis. DESIGN Histone deacetylase-1 target mRNAs that were up-regulated by valproic acid (VPA) treatment in endometriotic cyst stromal cells (ECSCs) were identified by a global mRNA microarray technique. RESULTS We identified 5 candidate genes and chose CCAAT/enhancer-binding protein α (C/EBPα) for further functional experiments. C/EBPα mRNA and protein expression is attenuated in ECSCs, and the expression was up-regulated by VPA stimulation. Immunohistochemical stainings also confirmed the decreased staining for C/EBPα protein in endometriotic tissues. VPA treatment resulted in an accumulation of acetylated histones H3 and H4 in the promoter region of the C/EBPα gene in ECSCs. The compulsory expression of C/EBPα in ECSCs directed the inhibition of cell proliferation and the induction of apoptosis. C/EBPα knockdown by small interfering RNA directed the stimulation of cell proliferation and the resistance to apoptosis in normal eutopic endometrial stromal cells. The expressions of peroxisome proliferator-activated receptor-γ (PPARγ), period homolog 2 (PER2), p53, apoptosis-inducing factor, mitochondrion-associated 1 (AIFM1), Bax, caspase-8, caspase-10, p16(INK4a), p21(Waf1/Cip1), cyclin-dependent kinase (cdk) 2, and cdk4 were down-regulated by C/EBPα knockdown. CONCLUSIONS Our findings suggest that an epigenetically suppressed tumor suppressor gene is involved in the pathogenesis of endometriosis by creating the proliferative, antiapoptotic, and other disease-specific characteristics of endometriosis. The results also suggest that histone deacetylase inhibitors are promising agents for the treatment of endometriosis.

Metastatic Uterine Cervical Cancer Originating in the Lung: A Case Report

We report a case of primary pulmonary adenocarcinoma which metastasized to the uterine cervix. A 69-year-old postmenopausal Japanese female was admitted to our hospital because of general fatigue and atypical genital bleeding. Four years before, she had undergone video-assisted thoracoscopic right upper lobectomy, for primary lung cancer (adenocarcinoma), stage IIIb, pT3N1M0. Gynecologic investigation showed a cauliflower-like tumor in the uterine cervix and parametrial invasion towards the bilateral pelvic wall. Metastasis of extragenital carcinoma to the cervix uteri is rare. Most such reported cases originated in the breast and gastrointestinal tract. In this case, cervical biopsy specimens were revealed to be adenocarcinomatous, similar in pathological features to the previously resected lung cancer. Immunohistochemical staining was positive for thyroid transcription factor-1 and pulmonary surfactant apoprotein A and negative for CA125 and thyroglobulin. Although rare, the respiratory tract should be considered as a possible primary site of uterine cervical metastatic carcinoma.

The production of VEGF involving MAP kinase activation by low level laser therapy in human granulosa cells.

OBJECTIVE The function of granulosa cells is regulated by various hormones and growth factors. Our aim is to clarify the regulation of vascular endothelial growth factor (VEGF) production via mitogen-activated protein kinase (MAPK) induced by low level laser therapy (LLLT) in human granulosa cells. METHODS A human granulosa cell line, KGN cells, were cultured and incubated after LLLT (60mW, GaAlAs 830nm). The levels of VEGF in the culture media were determined by an enzyme-linked immunosorbent assay. The activation of MAP kinase in KGN cells was detected by western blot analysis. RESULTS VEGF production was significantly increased by LLLT in a time-dependent manner. MAP kinase activity was increased by LLLT. In addition it was enhanced by LLLT and follicle-stimulating hormone (FSH) stimulation. CONCLUSIONS The results suggested that VEGF is induced by LLLT through mechanisms involving MAPK. The increase in VEGF may contribute to neovascularization, which in turn would promote various ovulation phenomena as well as follicular growth.

Death receptor 6 is epigenetically silenced by histone deacetylation in endometriosis and promotes the pathogenesis of endometriosis.

The purpose of this study is to evaluate the involvement of death receptor (DR) 6 in the pathogenesis of endometriosis.

Combined large-cell neuroendocrine carcinoma and endometrioid adenocarcinoma of the endometrium: A case report and survey of related literature.

Primary large‐cell neuroendocrine carcinoma of the endometrium is extremely rare and has a poor prognosis. This report describes a case of combined large‐cell neuroendocrine carcinoma and endometrioid adenocarcinoma of the endometrium diagnosed as stage IIIA. The patient underwent surgery and chemotherapy and has been well with no evidence of disease for 20 months. The optimal treatment for this rare tumor has not been established. Considering its rarity and variability, it is difficult to establish an evidence‐based therapeutic regimen.

Decidualization Differentially Regulates microRNA Expression in Eutopic and Ectopic Endometrial Stromal Cells

Decidualization of the endometrium and endometriosis involves the morphological and biochemical reprogramming of the estrogen-primed proliferative stromal compartment under the continuing influence of progesterone. Here, we evaluated the involvement of microRNA in the decidualization processes of normal endometrial stromal cells (NESCs) and endometriotic cyst stromal cells (ECSCs). In vitro decidualization of NESCs and ECSCs was induced by long-term culture with a combination of 0.5 mmol/L of dibutyryl cyclic adenosine monophosphate and 100 nmol/L of dienogest. We investigated the effect of in vitro decidualization on the microRNA and messenger RNA (mRNA) expression profiles of the NESCs and ECSCs using global microarray techniques and an Ingenuity Pathways Analysis. Decidualization differentially enhanced the miR-30a-5p expression in the NESCs and the miR-210 expression in the ECSCs. The enhanced miR-30a-5p expression in the NESCs correlated with the increased mRNA expression of Krüppel-like factor 9 and period circadian clock 3 as well as the decreased mRNA expression of tolloid-like 1, tolloid-like 2, and paired-like homeodomain 1. The enhanced expression of miR-210 in the ECSCs correlated with the decreased mRNA expression of growth hormone receptor and thymidine kinase 1. Although there is no direct evidence, we speculate that the loss of miR-30a-5p-mediated mechanisms of decidualization and the acquisition of miR-210-mediated mechanisms of decidualization may be involved in the progesterone resistance in endometriosis. Further investigations are necessary to test this speculation.

Treatment and prognosis of bone metastasis from cervical cancer (KCOG-G1202s)

The early and precise diagnosis and proper palliative treatment of bone metastasis is important for improving the quality of life of cervical cancer patients. The aim of this study was to clarify the clinical features, treatment modalities and prognosis of bone metastasis in cervical cancer patients in Japan.

Intravenous leiomyomatosis treated with radical hysterectomy and adjuvant aromatase inhibitor therapy

Intravenous leiomyomatosis (IVL), a rare disease that is histologically benign but clinically aggressive, is characterized by the intraluminal growth of benign leiomyoma in the intrauterine and systemic veins. Preoperative diagnosis of IVL is difficult, because the symptoms of early stage IVL are similar to those of uterine leiomyoma. The efficacy of adjuvant hormone therapy after surgical resection of IVL remains unclear. Herein is described a case of IVL that was diagnosed preoperatively, in which successful total resection of the tumor was achieved by radical hysterectomy. The patient, a 50‐year‐old premenopausal Japanese woman, also underwent aromatase inhibitor treatment and was free of disease at 36 months after surgery. Contrast‐enhanced computed tomography is suggested as the best assessment for identifying and diagnosing IVL. Radical hysterectomy can be considered a successful therapy for total resection. Aromatase inhibitor treatment may be effective, especially when the patient has not yet entered menopause.